1、ro,.RM No. A7Z16L.4. + -NACA-.-.RESEARCH .MEMORANDUMA WIN 70.9 20Asinwould be expected, the chord+xtension controls caused an increasethe longitudinal stability of the model.A ChordXExtensionControl and a ConventionalAileron on the Full-Span ModelIn order to obtain a comparison of the performance of
2、 the chord-etiension control with that of a conventional aileron, tests wereconducted upon the full-span model with a conventional aileron of2&percen chord and 5&percent span and with a chord+xtensioncontrol of 5&percent semispan similar to control A extended 16.Measuramnts were made of the rolling
3、moments at -f- -es ofyaw throughout the angle-of+ttack range and the rates of roll withthe model rotating unrestrained. It was found that at small anglesof attack control A, as tewted on the full-span model, W3Sincapable of producing steay,rates of roll with the nmdel unre-strained. Therefore, the c
4、ontrol was extended tangent to the uppersurface of the airfoil (referredto as control Al), therebyincreasing the control deflection relative to the wing chord plane.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM No. A7Z16from 255* to P18t.ex
5、tension control onof 18t.All the res+ts presented for the chord-the full-span model are for a deflection.7The rolling nt coefficients and the win#ip helix anglesmeasured with the chord+ tiension control Al and with the conven-tional ailerons on the full-span model are presented in figure 7.As shown
6、by these data, the ailerons were considerably more effec-tive than the chord-extension controls. Also the effectiveness ofthe chord+tiension control was seriously reduced as the angle ofyaw was increased. The wing=tip helix angles which the conventionalailerons me capable of producing were also estf
7、mated from themeasured rolling+mxmmt coefficients, using the damping In roll ofreference 3 reduced by the cosine of the sweepback angle. Theresults, shown in figure 7, indicate that simple sweep theory givesa good ffrst approximation of the damping in roll at small anglesof attack, but at higher ang
8、les of attack where the wing tip wasstalled the consequent reduction in the demping in roll should beconsidered.ByEans of a turbulence net andby varying the dynemicpressure from 5 to 50 pounds r square foot, the Reynolds nuderof the full-s model mS varied from 0.27 x l& to 2.08 x 10s.The effect of t
9、his variation of Reynolds nuniberon the witip helixangles producedby control Al is shown in figure 8.Spoilers on the Semispan ModelThs data from the tests of the spoilers of percent span onthe semlspan model are presented in figure 9. As shown by thesedata, the largest rolling+noment coefficients we
10、re masured for thespoiler perpendicular to the air stream. However, at high anglesof attack, there was either a complete reversal in spoiler effectiv-enessor the effectiveness was seriously reduced, depending on thespoiler location. The spoilers were comiderably more effective atlow angles of attack
11、, but were less effective at high angles ofattack than the chord+xtension controls. The conventional aileronstested on the full-span model were mare effective than any of theother controls tested.Fences on the Semispan ModelDuring the course of the investigati& fences were tested on theupper surface
12、 of the semispan model in an effort to extend thelineerity of the pitihing+nnt characteristicsto higher liftcoefficients. As shownby the data in figure 10, the fences didProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-8 NACA NO. A7L16extend the linea
13、r variation of pitching+mment coefficientwith liftcoefficientfrom a lift coefficient of 0.45 to 0.80. However, thelongitudinal stabilityat higher lift coefficientswas not imyroved.CONCLUSIONSThe results of the wind-tunnel investigation of several lateral-control devices and fences on a 45 swepkack w
14、ing of aspect ratio4.5 and of taper ratio 0.5 indloate:10 The conventionalailerons were more effective in producingrolling moments than either the chord-extension controls or thespoilers throughout the useful angle-of+ttack range.2. The maximum effectiveness of the spoilers in producingrolling momen
15、ts was obtainedwith the syoilers perpendicular to theair stream. .3. Simple sweep theory provided a good first approxhation ofthe damping in roll at small angles of at&ck, but was unsatisfactoryfor redicthg the damping in roll at higher angles of attaok whenthe wing was p=tially stalled.4. The fence
16、s parallel to the air stream increased the maximumlift coefficient for a linear variation of pltching+nmumt coefficientwith lfft cmfficlent from 0.45 to 0.80, but caused no improvementin the longitudinal stability at higher lift coefficients.Ames Aeronautical Laboratory,National Advisory Committee f
17、or Aeronautics,Moffett Field, CalIf.REFERENCES1. Letko, William, and Goodman, Alex: Preliminary Wind-TunnelInvestigational Low Speed of Stability and Control Characte&istics of Swept+ack Wings. NACATW NO. 1046, lg46.2. Swanson, Robert S., and Toll, Thoms A.: Jet-Boundary Correc-tions for Reflection-
18、Plane Models in Rectangular Wind Tunnels.NACAARR NO. 3E22, 1343.-.u3* Swanson, Robert S., and Priddy, E. LaVerne: Lifting-Surface-Theory Values of the Damping in Roll and the Parsmter Used inEstimating Aileron Stick Forces. NACAARR No. L23, 1945. .Provided by IHSNot for ResaleNo reproduction or netw
19、orking permitted without license from IHS-,-,-NAC!A.RM NO. i17z16TABLE I.- GEOMETRY OF MODELSDimsnsion Ssmispan wing N1-span wingAspect ratio 4.-5 4.5Tar ratio a715 .5Sweepback of 0.25-ohordline, degrees k5 45Airfoil section NAC!A NACA64A210 (a=O.8) 64A21o (a=o.8)Spare,feet 4 3Area, square feet 7.09
20、7 1.956Mean aerodynamic chord,feet 1.844 .692Root chord, feet 2.371 .889Tip chord, feet 1.185 .444.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-10 NACA RM NO. A7L16.TABIZ II.- DIMENSIONAL DATA E(IRCHQRXEX!L!ENSIONCON!lROM ON TEE SEMISPAN MODELAngl
21、e between wingControl Control span traili edge and AreaWing semispan ccnxtroltrailing edge (Sqft)in plan view (deg)A 0.50 16 0.87A .50 11 .5*A. .50 6 .326B .44 16 .74c .50 0 (Constant+hora a7155control)D 1.00 8 1.74.Provided by IHSNot for ResaleNo reproduction or networking permitted without license
22、 from IHS-,-,-NACA RM No. A7Z16 EL*.p-qm:._(a) Phin wing.4:+- : -,-: . .-, .+-. :., . .- 4-105.11(b) Control A extendedFigure l.- Semispam model mounted in the Ames 7 by 10-foOt wind tunnel.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Provided by
23、IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-1.,. -j/ ha,bi t.,.A-L A-10W4(a) ConventioMl ailerons defleoted (b) Control A. ertentledFigure 2. Full-span mcdel mounted on the sting in tlm AIES 7- by l&foot wind tunnel.Provided by IHSNot for ResaleNo reproducti
24、on or networking permitted without license from IHS-,-,-.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-.ItMM RM No. ATLL6 15- . r-/2“55 .091L .-.? kdSection A-A, no scaleControl C Control DAil dimensions in inches =&=Rgure 3.- Chord-extension contr
25、ols tested on semispan model.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Pm-iSoilefBc/ /1Note (All dimensions in inches(2) Fences and spoilers extended / inchdove the wing surfoce.Rgure 4- Spoilers umf fences tesied on the semispt7n model.t (,! I
26、Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM No. A7L16 170If4 8 12 /6Q -4 0figure 5.-Effect ofsemispi?n model.Angle of ,attuck,chord-extension controlReff = L88 z /08.20 24 28a, deg.A on aerodynomlc characteristics of theProvided by IHSNot
27、 for ResaleNo reproduction or networking permitted without license from IHS-,-,-i&QkpProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM Noe A7L16.3o 09 Unflagged sym.Ailerons -a75 16” Flagged sy?n./ / /o1 - Computed from rolling-moment coef-, fi
28、clants produced byailerons.180 4 8 12 /6 20 24Angle of uttuck, a, deg.Figure Z- ComparisonQ/?d Wing-tip helixextension controlof rolling-moment coefficientsonghSroouce by ChOrO-41 und conventional oilerons19on the full-spun model. /?eff = /.88x10?Provided by IHSNot for ResaleNo reproduction or netwo
29、rking permitted without license from IHS-,-,-.20 n)0.2 .4 .6 .8 1! 12Ef fecthe Reynolds/.4 L6 /.8 2.0 22Number x /0-6Figure 8.- Effect of Reynolds number on vohes of wing-tip helix ongle :by chord- exhw?sion control A, on the full-spun model m.r ,Provided by IHSNot for ResaleNo reproduction or netwo
30、rking permitted without license from IHS-,-,-9 .II-htntmtmtP=BmProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-22 NACARM No. A600-.2IO .04 .08 .12 .16 .20 .24 .28 .32 .36 .40 .44 .48Drag coefficient, CDFigure IO.- Effect of upper-surface fences on the aerodynamic choructerlstlcs of thesemispan model. Reff = 1.88 X 10!Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
